Analysis of Water Availability and Use for Solar Power Production in Nevada

Solar energy is emerging as a popular source of clean energy and represents a viable option to meet energy demands of Southwestern U.S., characterized with abundant sunshine. Technological advancements have made solar power efficient and economically competitive with the traditional thermoelectric power plants. Utility-scale solar plants may generate electricity by using the photovoltaic (PV) or concentrated solar power (CSP) systems. However, solar systems need water to wash the panels/mirrors to maintain their efficiency. Water use in CSP plants for wet or hybrid cooling processes is comparable to that in thermoelectric plants. Hence development of solar power may be curtailed in the semi-arid southwestern regions because of limited water resources and changing climate. This study used a system dynamics model to analyze water issues of the state of Nevada for development of solar power under the renewable portfolio standard (RPS). Water availability and use for different scenarios of PV and CSP were quantified to meet the RPS goals during the period 2010–2030. Land requirements and subsequent reduction in CO₂ emissions due to solar power development were also evaluated. Results showed that transitioning to solar technology from coal led to substantial reductions in CO₂ emissions during the period 2010–2030. CSP tower have the largest land requirements, whereas linear Fresnel have the smallest land requirements. Generating electricity using PV plants as well as using dry cooling methods for CSP plants was found to be better options for water stressed areas. This model can also be applied to other regions using appropriate datasets.